Thermodynamic and spectral properties of DNA miniduplexes with the terminal G x A mispairs and 3' or 5' dangling bases.
The tetradeoxyribonucleotide pAGCG in 1 M NaCl forms duplexes with terminal non-canonical pA x G pairs with stability significantly exceeding that for the duplex (pAGCT)2 and lower than that for the duplex (pCGCG)2. The deoxyriboduplex (pAGCG)2 is considerably stabilized by 3'-Y and slightly by 5'-X dangling bases. Therefore, the stability of duplexes with 3' dangling bases decreases in the order (pAGCGY)2 > (pCGCGA)2 > (pAGCTA)2. The sum of the independent stabilizing effect of the of 5'-pG and 3'-A dangling bases on the (pAGCG)2 core duplex is higher than that of the additional terminal pG x A pair in pG-A-/-G-A tandem of the duplex (pGAGCGA)2.
Lokhov
S G
SG
Institute of Bioorganic Chemistry, Siberian Division, Russian Academy of Science, Novosibirsk. lokhov@modul.bioch.nsk.su
Pyshnyi
D V
DV
D001482:Base Composition / Q000235:genetics*; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis / Q000737:chemistry; D013053:Spectrophotometry; D013816:Thermodynamics
D009838:Oligodeoxyribonucleotides; D004247:DNA